Various means have been used in the prior art to semiautomatically successively fire a plurality of projectiles from a launcher. One of the prior art means for triggering a multitube launcher utilizes a trigger handle assembly having a bellcrank linkage connected to a ratchet drive means which has an extension shaft joining the ratchet drive to a firing pin rotating cam mechanism. The aforementioned device used a rear cocking knob to precock each of the firing pins. Each pull of the trigger by an operator released one firing pin which then in turn fired the next round from the multitube launcher.
The problem with the aforementioned prior art caming mechanism was that rear hand cocking of the firing pins was a safety hazard. The system often required placing the operator's hand behind the gun in the backblast area of the rocket motor and subjected the operator to possible injury in the event of an inadvertent rocket motor firing. An unexpected firing could occur when the firing pin cam follower was stuck on the cam firing lobe peak in a "hand-fire" condition. The problem with prior art cocking devices which were located in the front or side of a multitube launcher was that they generally require the installation of additional linkages which are complex to design and costly to install.